Determine the identity of the daughter nuclide from the alpha decay of Th.

Question

Quizplus · Accepted Answer

Alpha decay results in the emission of an alpha particle, which is a helium nucleus (consisting of 2 protons and 2 neutrons). Therefore, the daughter nuclide will have an atomic number that is 2 less than the parent nuclide and an atomic mass that is 4 less. In this case, the parent nuclide is 11Th with an atomic number of 90 and an atomic mass of 229. Thus, the daughter nuclide will have an atomic number of 88 (90-2) and an atomic mass of 225 (229-4). The only choice that matches this criterion is C, 11Ra, which has an atomic number of 88 and an atomic mass of 225.

Determine the Identity of the Daughter Nuclide from the Alpha